Printer technology is continually advancing, resulting in commercially available printers with increasing speed, print quality, features, etc. A wide range of printers are commercially available, ranging from relatively inexpensive "desktop" models with few features to more expensive "printing press" models with many features and expandable options.
One problem facing many modem printers, especially the larger models, is controlling the transfer or flow of paper through the printer. The print medium is physically transferred through one or more devices in the printer. This physical path of the paper through the printer is typically referred to as the "print path" or "print medium path". Many printers either include or can be expanded to include additional features by adding input and/or output devices to the printer. For example, an additional input device may physically stamp each page being printed, or an additional output device may sort and/or fold pages after printing. As additional input and/or output devices are added to the printer, the number of print paths available in the printer increases. For example, a printer with an output device to fold pages would typically have at least two print paths, one in which the pages are fed through the output device (either folding or not folding the page), and another in which the pages are not fed through the output device.
A controller(s) within the printer communicates with the various devices in the printer to feed the pages through the proper print paths. One way to perform such communication is to "baby-sit" the print medium as it traverses a print path. The controller communicates with each of the individual devices in that print path one at a time, providing each with information regarding what, if anything, the device should do with the print medium (i.e., either pass the print medium through to another device or output the print medium directly). Such "one to one" communication, however, is burdensome on the controller and is made even more so with each new device that is added to the printer.
The invention described below addresses these and other problems, using print path identifiers to identify print paths in a printer.